Aerodynamic stall

Surge is quite similar to aerodynamic stall. Of course, when a compressor surges, its rotor does not stop spinning. The rotor is spun by the motor. But when the flow of gas through the rotor falls below a certain rate, the forward velocity of the gas stops. With no flow, there is no velocity to convert to feet of head. Then, the AP developed by the compressor falls to zero. 

The NTSB investigators determined that the accident s probable cause was the captain s inappropriate response to the activation of the stick shaker, which led to an aerodynamic stall from which the airplane did not recover. 

As the plane s air speed is reduced, its ability to maintain a lift equal to its weight is reduced. At some reduced speed, the plane s lift then becomes insufficient to keep it flying. The aircraft undergoes aerodynamic stall. The plane falls out of the sky, crashes, and all the passengers are killed. 

Chapter 35 Centrifugal Compressors and Surge 429 35.1.3 Aerodynamic Stall... 

The form of a wind turbine power curve is shown in Figure 2.2. The wind turbine starts producing electricity when wind speed exceeds the cut-in threshold. From that point up to the nominal wind speed, power increases proportionally to the cube of wind speed. For higher wind speeds, power is kept close to the nominal value due to the blades aerodynamic design (passive stall control). Alternatively, a... 

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